Wetness indicating roll wrap system, and methods

ABSTRACT

A wetness indicating wrap system that provides evidence to the user if the roll wrap system has been exposed to water or other aqueous material. The wetness indicating wrap system includes a water contact indicator (e.g., soluble dye present as indicia) on an outer surface of the roll wrap system, the water contact indicator configured to bleed, run, or otherwise distort when exposed to water or other aqueous material. The water contact indicator dries in its distorted image, thus providing an indication that the water contact indicator, and thus the roll wrap system, had been exposed to water or other aqueous material.

The present disclosure is directed to rolls of sheet good products, such as rolls of paper sheet goods. The disclosure relates to wrap systems for the rolls.

BACKGROUND

Paper rolls, or other rolls of sheet material, usually have the roll covered with a roll wrap protective system, such as a sheet (i.e., an outer wrap) wrapped around the circumference of the roll. Any wrap material overhanging the ends of the roll is usually crimped radially inwardly over the ends of the roll. A header assembly may be located internally and/or externally of the crimped over projecting wrap portion at each end of the roll. This protection system, including the roll wrap and the header assembly, is common.

The roll wrap system protects the roll of material (e.g., paper) throughout the storage and distribution process. Once a roll of material is formed, it is desirable to cover the roll to protect the material from damage until it is used.

It is common that during storage or shipping, the wrapped roll may come into contact with water, for example, as a puddle on the floor on which the roll is stored, rain or snow falling on the roll during transport, or the like. Many times, the water soaks through the roll wrap and/or header and contacts the material, damaging the material.

As mentioned, paper is a common rolled material that is wrapped with a roll wrap system for storage and transportation. Wet paper can generally not be used. Even after drying, however, although the paper may have not visible indication of damage, the paper may no longer be suitable for use or may not perform as expected. Often, the paper dries before it has been noticed that it had been wet, thus creating a surprise for the paper user when the paper roll is unwrapped.

What is needed in a system to notify one if a wrapped roll has been exposed to water or other aqueous material.

SUMMARY

The present disclosure provides a roll wrap system that provides an indication to the user if the roll wrap system has been exposed to liquid water or other aqueous material. The wetness indicating wrap system of this invention includes a water contact indicator on an outer surface of the roll wrap system, the water contact indicator configured to bleed, run, or otherwise distort when exposed to water or other aqueous material. The water contact indicator dries in its distorted image, thus providing an indication that the water contact indicator, and thus the roll wrap system, had been exposed to liquid water or other aqueous material.

Having evidence that the roll has been exposed to liquid water, and possibly damaged, has numerous benefits.

Having a water contact indictor on the roll wrap system increases the confidence level of the user of the roll material that the material has not been exposed to liquid water and thus not damaged or rendered unusable. Further, knowing that the roll of material has not been damaged, those handling the roll may be more careful than if they were not certain the material was still useable, quality material. Also, those handling the roll may be more careful knowing that it would be traceable back to them if water contact occurred while the roll was under their control. As possession of the rolls passes from one to another, the subsequent handler would know if the roll was damaged prior to his possession of the roll, thus providing an indication of under whose control the damage occurred. Knowing where and when water damage occurred would also save time and money, reducing the handling and transport of damaged rolls.

One particular embodiment of this disclosure is a wetness indicating wrap system that includes a roll wrap system having a water contact indicator thereon. The roll wrap system includes a roll wrap and at least one header (often two headers), with the water contact indicator on at least one of the roll wrap and the at least one header. The water contact indicator may be indicia formed from a water soluble dye.

These and other embodiments are described in the present disclosure.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic perspective view of a roll of sheet material;

FIG. 2 is a partially exploded, schematic perspective view of a roll having a roll wrap system, the roll wrap system including an outer protective roll wrap, an optional inner header, and an outer header;

FIG. 3 is a schematic perspective view of a roll having the wetness indicating wrap system of the present disclosure; and

FIG. 4 is the roll of FIG. 3 after having been exposed to a water or aqueous liquid source, showing the benefits of the wetness indicating wrap system of the present disclosure.

DETAILED DESCRIPTION

The present disclosure is directed to providing evidence of water exposure to a wrapped roll, particularly a paper roll, such as those from a paper making processes.

The size of these rolls is often 30-60 inches in diameter, 30-100 inches in height, weighing from less than a ton to as much as 5 tons, although smaller and larger rolls are also common. Often used terms for these rolls include trim, master and roll stock.

Referring to FIG. 1, a standard, unprotected trimmed roll of paper is illustrated at reference numeral 10. Paper roll 10 has a first end 12, an opposite second end 14, and an outer surface 15 that extends between ends 12 and 14. Paper may be wound on a core or be wound in a coreless manner to form roll 10. The paper of paper roll 10 may be any conventional or otherwise known paper, and of any basis weight that can be wound into a roll, such as kraft paper, newspaper, or other. The paper may be bleached or unbleached, or colored. The paper may be in any stage of processing, for example, ready for printing, ready for slitting, already slit to the desired size, or ready for any other converting process. Methods for forming paper roll 10 are well known.

Rolls 10 are often stored and moved from one location to another for storage. To protect rolls 10 during handling and storage, a protective outer covering system, that may include various elements, is added to roll 10.

FIG. 2 illustrates wrapped paper roll 10′, which is roll 10 having a roll wrap system, comprising various protective elements, present. In particular, wrapped roll 10′ includes an outer protective wrap 20 that extends around the circumference of roll 10. Outer protective wrap 20 preferably extends axially over ends 12, 14 of roll 10 to form covered end 22 and covered end 24, respectively. The portion of wrap 20 that extends over ends 12 to form covered end 22 is usually crimped or folded to form portions 42. Covered end 24 has a similar overlap of wrap 20, but is not seen in FIG. 2. Outer protective wrap 20 and methods of applying to roll 10 to form crimped portions 42 over covered ends 22, 24 are well known.

It is also well known to apply a header assembly to one or both ends 22, 24 of wrapped roll 10′, to protect the edge of the rolled material. The header assembly often includes an inner header, positioned between the rolled paper and crimp portions 42, and an outer header, positioned over crimp portions 42. In some assemblies, only one header is present. FIG. 2 illustrates an inner header 50 at end 22 present between the rolled paper and crimp portion 42. A comparable inner header can be present at end 24. The header assembly also includes outer header 55, which is illustrated removed from end 22, to facilitate understanding of the placement of outer header 55 on wrapped roll 10′. Header 55 is typically circular, to match the shape of end 22 of the paper roll. The outer perimeter of header 55 may extend short of the outer perimeter of end 22 and wrap 20, thus leaving exposed a portion of crimped portions 42, or, outer header 55 may cover the entire end 22 and crimped portions 42.

Any or all of wrap 20, inner header 50 and outer header 55 can include natural fiber, synthetic fiber, or a mixture.

Natural fiber refers to fiber formed from plants or animals. Natural fibers are not fibers that are formed as a result of extrusion or spinning. The natural fibers can be obtained from a source of fiber using techniques such as chemical pulping, chemical mechanical pulping, semi chemical pulping, or mechanical pulping. Natural fibers from plants are often referred to as cellulosic fibers. Exemplary natural fibers that can be used to form base sheet 11 include wood fibers and non-wood natural fibers such as vegetable fibers, cotton, various straws (e.g., wheat and rye), various canes (e.g., bagasse and kenaf), silk, animal fiber, (e.g., wool), grasses (e.g., bamboo, etc.), hemp, corn stalks, abaca, etc.

Wood fiber can be obtained from wood pulp, which can include hardwood fibers, softwood fibers, or a blend of hardwood fibers and softwood fibers. The pulp can be provided as cellulose fiber from chemical pulped wood, and can include a blend from coniferous and deciduous trees. By way of example, wood fibers can be from northern hardwood, northern softwood, southern hardwood, southern softwood, or any blend thereof. Hardwood fibers tend to be more brittle but are generally more cost effective for use because the yield of pulp from hardwood is higher than the yield of pulp from softwood. Softwood fibers have desired paper making characteristics but are generally more expensive than hardwood fibers.

The natural fibers can be extracted with various pulping techniques. For example, mechanical or high yield pulping can be used for stone ground wood, pressurized ground wood, refiner mechanical pulp, and thermomechanical pulp. Chemical pulping can be used incorporating kraft, sulfite, and soda processing. Semichemical and chemi-mechanical pulping can also be used which includes combinations of mechanical and chemical processes to produce chemi-thermomechanical pulp. Natural fibers can be bleached or unbleached.

The pulp can include a recycle source for reclaimed fiber. Exemplary recycle sources include post-consumer waste (PCW) fiber, office waste, and corrugated carton waste. Post-consumer waste fiber refers to fiber recovered from paper that is recycled after consumer use. Office waste refers to fiber obtained from office waste, and corrugated carton waste refers to fiber obtained from corrugated cartons. Additional sources of reclaimed fiber include newsprint and magazines. Reclaimed fiber can include both natural and synthetic fiber. Incorporation of reclaimed fiber in base sheet 11 can aid in efficient use of resources and increase satisfaction of the end user of masking paper 10.

Examples of synthetic fibers that could be used for any or all of wrap 20, inner header 50 and outer header 55 include polyacrylic fiber, polyethylene fiber, polypropylene fiber, polylactide fiber, rayon, and nylon fiber.

In accordance with this disclosure, the wrap system, comprising wrap 20 and at least outer header 55, includes a water contact indicator thereon. A water contact indicator is a visible element that, when exposed to liquid water, distorts, usually in its shape. The water contact indicator sufficiently distorts upon exposure to liquid water so that a user can readily recognize the distortion. The water contact indicator does not return to its pre-distorted form upon removal of the water or drying. One example of a water contact indicator is indicia formed from a water soluble dye.

Referring to FIG. 3, a paper roll wrapped with the wetness indicating wrap system of this disclosure is illustrated as roll 100. Roll 100 includes first end 112 on which roll 100 is placed and opposite second end 114 at the top of roll 100. Roll 100 has thereon a roll wrap system that includes a water contact indicator. In this specific embodiment, roll 100 includes a roll wrap system comprising an outer wrap 120 that includes indicia 130 thereon. The header at end 114 also includes indicia 130 therein. Although not seen in this view, the header at end 112 may additionally or alternately include indicia 130 thereon.

Indicia 130 may be any readily visually discernable marking, such as alphanumeric indicia, (i.e., letters or numbers), shapes (e.g., polygons), lines, patterns (e.g., cross-hatch) or irregular arrangements of shapes or lines, etc. Although indicia with fairly exact patterns or lines is preferred (in order to readily discern if the indicia has bled or run or otherwise distorted), large solid areas of indicia may be suitable. In this embodiment, indicia 130 includes alphanumeric indicia 132 (particularly, “PAPER”) and cross-hatched lines 134 on wrap 120 and alphanumeric indicia 136 on the header. Of course other forms of indicia are suitable. Indicia 130 may relay information about the paper within roll 100, for example, lot number, date of production, basis weight, etc.

The water contact indicator, such as indicia 130, is preferably sufficiently large (e.g., at least 2 inches high, e.g., at least 3 inches high) and sufficiently bold so that one can readily visually inspect the quality of the water contact indicator at a distance of at least about 3 meters, often at a distance of at least 5 meters.

In most embodiments, the entire surface of the wrap system will include water contact indicator, such as indicia 130, however, in some embodiments, it may be desired to have the water contact indicator focused at end 112, the end that will be positioned on the ground or other supporting surface. Either or both of wrap 20 and outer header 55 can have the water contact indicator thereon; it is not required that the water contact indicator be the same on wrap 20 as on header 55.

In one embodiment, indicia 130 is formed on the wrap system, i.e., either or both of wrap 20 and outer header 55, from a water soluble dye. In preferred embodiments, the dye is a water soluble food grade dye.

A dye can generally be described as a colored, liquid substance that has an affinity to the substrate to which it is being applied. Dye is generally an aqueous solution, and may require a mordant to improve the fastness of the dye on the substrate (e.g., paper fiber). Both dyes and pigments/inks appear to be colored because they absorb some wavelengths of light while reflecting others.

A dye is different than an ink or pigment, which is a suspension or dispersion of finely divided pigment in a drying oil. Some types of inks dry by evaporation of a volatile solvent rather than by oxidation and polymerization of a drying oil or resin. In contrast with a dye, an ink or pigment generally is insoluble, and has no affinity for the substrate.

An example of a suitable, food grade water soluble dye for the wrap system of this disclosure is available from Sensient, located in Saint Louis, Mo. This dye is available in powder form which can then be blended into a solution. Water, other aqueous solvent, or organic solvent may be used.

The dye may be a natural dye, such as an organic colorant obtained from an animal or plant source. Examples of natural dyes include madder, cochineal, logwood, and indigo. The dye may be generally any color that is distinguishable from the wrap system surface on which it is applied. Colors that have the most contrast, as compared to the wrap system surface, would be most preferred.

The water contact indicator bleeds, runs, or otherwise distorts when exposed to liquid water or other aqueous source. Upon removal of the water or other aqueous source from the water contact indicator (that is, the area is dried), the water contact indicator does not return to its original form, but remains distorted. The water contact indicator should not bleed, run or otherwise distort under typical atmospheric conditions and preferably does not bleed, run or otherwise distort at relative humidity of less than about 90%.

In FIG. 4, roll 100 from FIG. 3 is illustrated contacting water or other aqueous material source. In FIG. 4, roll 100′ has first end 112 at least partially seated in a puddle of water W. It should be understood that other sources of water or other aqueous material would cause indicia 130 to distort; for example, water dripping onto roll 100 or seeping up through the floor.

As seen in FIG. 4, water W has contacted and at least partially wetted the wrap system surrounding the paper roll; water W may or may not have soaked through the wrap system and wetting the paper itself. Because of the exposure of indicia 130 on wrap 20 to water W, at least a portion of indicia 130 has distorted (e.g., run, bleed, etc.). The alphanumeric indicia (i.e., “PAPER”) has distorted, creating distorted alphanumeric indicia 132′. The edges of the individual letters are no longer sharp. In fact, some adjacent edges of the letters have bled together. In other embodiments, the individual letters may not be discernible. Additionally, the cross-hatch pattern alternating with the alphanumeric indicia has distorted, creating lines 134′. Indicia 136 at end 114 has not contacted water W and thus has not distorted.

After removal of paper roll 100′ from water W, paper roll 100′ will eventually dry, and in some embodiments, there will be little or no evidence remaining on roll 100′ that the roll had been exposed to water. The water contact indicator however, as indicia 130′, will remain distorted, providing visual evidence of prior wetting of the paper roll.

The dye that forms indicia 130 can be applied to wrap 20 by conventional coating processes, such as by flexographic coating, gravure coating, lithography, offset printing or other printing, knife coating, reverse angle gravure coating, and the like, and then appropriately dried or cured to drive off the dye solvent and set the dye to the substrate. Examples of suitable drying methods include using deck driers, ovens, steam or oil heated cans, or any combination thereof.

In most embodiments, a coating process is used that provides sufficiently sharp and precise edges for indicia to discern when indicia 130 has distorted. A size coat or other undercoating may be present on wrap 20 or header 55 prior to applying indicia 130. The application of indicia 130 onto the wrap system is usually done prior to applying the wrap system to the paper roll to be protected.

Coating speeds for indicia 130 of 100 ft/min to even 1000 ft/min can be obtained. The amount of water soluble dye applied to the wrap system is an amount sufficient to provide visually discernible and recognizable indicia 130.

The above specification, examples and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended. 

1. A wrapped roll of sheet material comprising: (a) a roll of sheet material having a first end and an opposite second end; and (b) a wetness indicating wrap system comprising a roll wrap system at least partially covering the roll, the roll wrap system having a water contact indicator thereon and comprising an outer wrap of material wrapped circumferentially around the roll and an outer header covering at least one end of the roll.
 2. The wrapped roll of claim 1 wherein each of the outer wrap and the outer header has the water contact indicator thereon.
 3. The wrapped roll of claim 2 wherein the outer header comprises a first header covering the first end of the roll and a second header covering the second end of the roll.
 4. The wrapped roll of claim 3, wherein each of the outer wrap, the first header and the second header has the water contact indicator thereon.
 5. The wrapped roll of claim I wherein the water contact indicator comprises indicia formed from a water soluble dye.
 6. The wrapped roll of claim 5 wherein the water soluble indicia is alphanumeric.
 7. The wrapped roll of claim 5 wherein the water soluble indicia comprises a repeating pattern.
 8. The wrapped roll of claim 1 wherein the sheet material is paper.
 9. A method of monitoring the quality of rolled sheet material, the method comprising: wrapping a roll of sheet material with a wetness indicating wrap system comprising a roll wrap system having a water contact indicator thereon; and monitoring the wrapped roll for distortion of the water contact indicator.
 10. The method of claim 9 further comprising, after wrapping, storing the wrapped roll.
 11. The method of claim 9 further comprising, after wrapping, transporting the wrapped roll from a first location to a second location.
 12. The method of claim 9 wherein wrapping a roll of sheet material with a wetness indicating wrap system comprises wrapping a roll of paper.
 13. The method of claim 9 wherein wrapping a roll of sheet material with a wetness indicating wrap system comprises wrapping a roll of sheet material with a wetness indicating wrap system comprising a roll wrap system having water soluble indicia thereon.
 14. A wrapped roll of sheet material comprising: (a) a roll of sheet material having a first end and an opposite second end; and (b) a wetness indicating wrap system comprising a roll wrap system at least partially covering the roll, the roll wrap system having a water contact indicator thereon and comprising at least one of an outer wrap of material wrapped circumferentially around the roll and an outer header covering at least one end of the roll.
 15. The wrapped roll of claim 14 wherein the roll wrap system comprises both an outer wrap of material and an outer header.
 16. The wrapped roll of claim 15 wherein each of the outer wrap and the outer header has the water contact indicator thereon.
 17. he wrapped roll of claim 15 wherein one of the outer wrap and the outer header has the water contact indicator thereon.
 18. The wrapped roll of claim 14 wherein the water contact indicator comprises indicia formed from a water soluble dye.
 19. The wrapped roll of claim 18 wherein the water soluble indicia is alphanumeric.
 20. The wrapped roll of claim 18 wherein the water soluble indicia comprises a repeating pattern. 